1. Field of the Invention
The present invention relates to a charger and controlling method thereof, and more particularly, to a wireless charger and controlling method thereof. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for displaying a charging area in further consideration of user's convenience.
2. Discussion of the Related Art
Generally, terminals can be classified into mobile/portable terminals and stationary terminals. The mobile terminals can be classified into handheld terminals and vehicle mount terminals again according to possibility of user's direct portability.
As functions of the terminal are diversified, the terminal is implemented as a multimedia player provided with composite functions such as photographing of photos or moving pictures, playback of music or video, game play, broadcast reception and the like for example.
A battery is necessary to operate the above-mentioned mobile terminal. A durable time of the mobile terminal depends not on a power line but on a battery power unlike a stationary terminal (e.g., a fixed type terminal).
Recently, for the convenience in using a mobile terminal, most of mobile terminals have chargeable batteries. In order to charge a battery of a mobile terminal according to a related art, a terminal supply system is used in a manner of connecting a cable to a charger terminal. In particular, the terminal supply system is a wired charging system that enables a battery to be charged by applying an AC power to a charger terminal.
If a power is supplied by the terminal supply system, particles cumulate in a battery due to a potential difference between a charger and the battery to cause the following problems. First of all, the particles cumulatively stacked in the battery degrade performance and life span of the battery and may cause a fire.
To overcome the above problems, many ongoing efforts are made to research and develop a contactless charger. Electromagnetic induction system has been introduced to commercialize the contactless charger in the early days. According to the electromagnetic indication system, a battery is charged based on the electromagnetic induction effect of coils provided to a charger and a mobile terminal. Yet, the contactless charger of the electromagnetic induction type has the following problems. First of all, a transmission distance for supplying a power by wireless is short. Secondly, the coil of the charger and the coil of the mobile terminal should be juxtaposed with each other.
To overcome the above problems, there are many ongoing discussions on a contactless charger of a magnetic resonance system. Compared to the electromagnetic induction contactless charter, the magnetic resonance contactless charger is advantageous in having a longer wireless charging distance and a high degree of freedom of transceiving coil placement.
However, according to the magnetic resonance system, there is no method of providing a user with information indicating a specific wireless chargeable range. The contactless charger using electromagnetic induction effect is developed into a pad configuration. If a mobile terminal is placed on a pad of the contactless charger, it is able to expect that the mobile terminal will be charged. On the other hand, it is not necessary for the magnetic resonance contactless charger to be developed into the pad configuration. If the magnetic resonance contactless charger does not have the pad configuration, it may cause a problem that a user has not idea about a place on which the mobile terminal should be placed to be charged.